Correction: High piezo-resistive performances of anisotropic composites realized by embedding rGO-based chitosan aerogels into open cell polyurethane foams

Correction for 'High piezo-resistive performances of anisotropic composites realized by embedding rGO-based chitosan aerogels into open cell polyurethane foams' by Tianliang Zhai et al., Nanoscale, 2019, 11, 8835–8844

Actuation Behavior of Multilayer Graphene Nanosheets/Polydimethylsiloxane Composite Films

The graphene nanosheets (GNS)/polydimethylsiloxane (PDMS) composite films with out-of-plane dielectric actuation behavior were prepared through a layer-by-layer spin coating process. The GNS-PDMS/PDMS composite films with 1~3 layers of GNS-PDMS films were spin coated on top of the PDMS film. The dielectric, mechanical, and electromechanical actuation properties of the composite films were investigated. The dielectric constant of the GNS-PDMS3/PDMS composite film at 1 kHz is 5.52, which is 1.7 times that of the GNS-PDMS1/PDMS composite film. The actuated displacement of the GNS-PDMS/PDMS composite films is greatly enhanced by increasing the number of GNS-PDMS layers. This study provides a novel alternative approach for fabricating high-performance actuators with out-of-plane actuation behavior

Melt Crystallization Behavior and Crystalline Morphology of Polylactide/Poly(ε-caprolactone) Blends Compatibilized by Lactide-Caprolactone Copolymer

Lactide-Caprolactone copolymer (LACL) was added to a Polylactide/Poly(ε-caprolactone) (PLA/PCL) blend as a compatibilizer through solution mixing and the casting method. The melt crystallization behavior and crystalline morphology of PLA, PLA/PCL, and PLA/PCL/LACL were investigated using differential scanning calorimeter (DSC) and polarized optical microscopy (POM), respectively. The temperature of the shortest crystallization time for the samples was observed at 105 °C. The overall isothermal melt crystallization kinetics of the three samples were further studied using the Avrami theory. Neat PLA showed a higher half-time of crystallization than that of the PLA/PCL and PLA/PCL/LACL blends, whereas the half-time of crystallization of PLA/PCL and PLA/PCL/LACL showed no significant difference. The addition of PCL decreased the spherulite size of crystallized PLA, and the nuclei density in the PLA/PCL/LACL blend was much higher than that of the PLA and PLA/PCL samples, indicating that LACL had a compatibilization effect on the immiscible PLA/PCL blend, thereby promoting the nucleation of PLA. The spherulites in the PLA/PCL and PLA/PCL/LACL blend exhibited a smeared and rough morphology, which can be attributed to the fact that PCL molecules migrated to the PLA spherulitic surface during the crystallization of PLA

Ultra-Light Reduced Graphene Oxide Based Aerogel/Foam Absorber of Microwave Radiation

We present the polarization-dependent highly absorptive in Ka-band composition of conventional polyurethane foam filled with in situ synthesized aerogel coated by reduced graphene oxide (rGO). The rGO-based aerogel was in situ prepared into the open-cell polyurethane foam (PUF) skeleton through a bidirectional freeze-drying process. The aerogel is composed of the flat lamellas stacks, possessing the anisotropic structure and unique electromagnetic properties. Further improvement of the electromagnetic shielding ability was possible by the rGO coating introduction as a coupling layer between PUF and rGO-based aerogel. This enhances the overall conductivity of the resulting composites: 1.41 + 3.33i S/m vs. 0.9 + 2.45i S/m for PUF loaded with in situ synthesized aerogel without rGO coating.With this mechanically robust plane easy to process coating one could achieve −20 dB by power with the record light structure (0.0462 g/cm2). That could compete in view of the weight per cm2 even with graphene-based absorbers comprising either dielectric matching elements or back metal reflectors, or both

Temperature and Voltage Dual-Responsive Ion Transport in Bilayer-Intercalated Layered Membranes with 2D Nanofluidic Channels

The controllable ion transport in synthetic membranes with nanofluidic channels by external stimuli has been attracting significant attention for nanofluidic diodes, biosensing, nanoreactors, and energy conversion. Here, we report a synthetic bilayer-intercalated layered membrane with two-dimensional (2D) nanofluidic channels, in which the ion transport can be controlled by external stimuli of temperature and voltage. The synthesis of the layered membranes includes the exchange of native cations in montmorillonite with the quaternary ammonium ions in a cationic surfactant and a subsequent vacuum filtration. The bilayer-intercalated interlayer spaces in the layered membranes act as 2D nanofluidic channels for ion transport. The phase state of the bilayers and the surface polarity of functionalized montmorillonite lamellae can be controlled by external temperature and voltage, respectively, which imbue the layered membranes with dual-responsive ion transport properties. Our dual-responsive layered membranes with 2D nanofluidic channels provide a new platform for creating smart synthetic membranes to control the ion transport